CXCR4 and HIV infectious disease: Furthermore, CXCR4 has been shown to function as a co-receptor for T cell line-tropic HIV-1 entry [17]; and for this reason, there has been considerable interest in the clinical potential of CXCR4 inhibitors such as bicyclam AMD3100 [18], horseshoe crab-derived peptide T22 [19], and the non-peptide TAK-779 [20] for inhibiting HIV infection.